JP2019007610A - Slewing bearing - Google Patents

Abstract

To provide a swing bearing including an improved seal, capable of being easily manufactured, and especially used under an operational environment exposed to powder dust or sewage water.SOLUTION: A swing bearing comprises: an inner ring and an outer ring; at least one row of rolling bodies arranged between the inner ring and the outer ring; and at least a labyrinth seal including seal means defining a closed annular space where the rolling bodies are arranged between the inner ring and the outer ring, and fixed to the inner ring or outer ring. A closed annular expansion chamber in the labyrinth seal is provided on the outside of the closed annular space of the rolling bodies. The swing bearing is configured to perform sealing with semi-solid material, liquid or gas in the closed annular expansion chamber.SELECTED DRAWING: Figure 1

Description

  The present invention relates to the field of bearings, and more particularly to a bearing provided with at least one row of rolling elements such as an outer ring, an inner ring, and a plurality of rollers provided between the outer ring and the inner ring.

  The present invention relates to a large-sized slewing bearing capable of rotating a movable part by a slewing bearing used in industrial machinery and equipment, tower cranes, specially equipped vehicles, and tunnel excavators.

  Patent Document 1 includes a row of rolling elements in which rolling elements are arranged between an inner ring and an outer ring, and a plurality of seals that define an annular space in which the rolling elements are closed between both wheels in the radial direction. Slewing bearings are disclosed.

JP2016-44814

The slewing bearing is of a type constituted by a contact seal.
In the slewing bearing constituted by the contact-type seal, when wear progresses on the contact surface of the seal portion, the seal is not sealed and foreign matter enters the closed annular space.

With the contact seal of the slewing bearing, under a specific operation, a fine foreign matter bites and damages the seal portion, and the foreign matter enters the closed annular space.
Contact seals have friction during rotation and have proven to be shorter in life than non-contact seals, as they enter from the outside under worn operation.

  Non-contact type seals used for slewing bearings. Narrow path seals and labyrinth seals have almost no change between low peripheral speed and static leakage at low speeds under low-speed operation conditions. Therefore, it has been proved that the sealing performance is not sufficient.

  From the above, as described in Patent Document 1, liquid such as sewage is restricted so as not to enter as close to the seal as possible. Absent.

  The labyrinth seal device is, for example, a staggered arrangement type, and includes a plurality of throttle sides provided on the rotating body side and the stationary body side. It is preferable to set a small gap (seal gap) between the tip of each aperture side and the surface facing this. However, if the seal gap is too small, the tip of the aperture side and the opposing surface come into contact with each other due to the influence of the difference in thermal expansion between the rotating body and the stationary body and the vibration of the rotating body, and the aperture side wears. As a result, the gap between the seals is expanded, that is, the sealing performance is deteriorated and leakage occurs.

  The present invention has been made paying attention to the above-mentioned problems, and it is intended to have a structure that can reliably prevent the intrusion of sewage and can sufficiently withstand use in a bad environment where rainwater or the like tries to enter the slewing bearing. To do.

  The inner ring 43 and the outer ring 37, at least one row of rolling elements 41 disposed between the inner ring 43 and the outer ring 37, and a closed annular space in which the rolling elements 41 are disposed between the inner ring 43 and the outer ring 37 are defined. Sealing means that is fixed to the inner ring 43 or the outer ring 37, and is at least a labyrinth seal 33, and the closed annular expansion space 32 in the labyrinth seal is disposed outside the closed annular space 40 of the rolling element 41. A slewing bearing provided with a structure in which the closed annular expansion space 32 is sealed with a semi-solid material, liquid, or gas, and the upper surfaces of the inner ring 43 and the outer ring 37 are provided with a deflector 39.

  The slewing bearing is damaged due to early wear of the raceway surface of the rolling element 41 and the outer ring 37 and the raceway surface of the inner ring 43 of the slewing bearing due to the fluid that shuts off the closed annular space 40 and the atmosphere side by providing the closed annular expansion space 32. The life of the replacement cycle is extended.

  The slewing bearing of the present invention is effective for extending the life of the slewing bearing because the cause of damage to the bearing due to contaminated particles such as sewage and dust is eliminated, and the replacement cycle of the slewing bearing becomes longer under specific operating conditions.

It is an axial fragmentary sectional view of the slewing bearing which provided the tooth | gear in the outer ring | wheel by embodiment of this invention.

The present invention will be described with reference to FIG.
This slewing bearing provides a closed annular expansion space 32 between the closed annular space 40 and the outside by putting liquid into the labyrinth seal 33. By using the auxiliary fluid pressure opposite to the direction, liquid intrusion such as sewage is prevented.

  The slewing bearing includes an inner ring 43, an outer ring 37, and a cage (not shown) that keeps a row of rolling elements 41 provided between the two rings at regular intervals in the circumferential direction. The inner ring 43 and the outer ring 37 are coaxial and extend in the rotation axis direction of the slewing bearing. The inner ring 43 and the outer ring 43 are solid. This slewing bearing is manufactured by rolling, heat treatment, grinding, cutting, welding, polishing, nitriding, plating, fusing, cutting, or the like by forging, casting, or roll.

  The inner ring 43 or the outer ring 37 is provided with a plurality of radial teeth 36 on either the inner ring 43 or the outer ring 37 and is fitted with a gear for changing the direction of the movable direction.

  In the illustrated embodiment, the inner ring 43 and the deflector 39 can be assembled by screwing the two assembly part ring bodies 39 and 43 together, but other mounting methods include fixing and welding by fitting. is there.

  The deflector 39 can be made of non-metal such as elastomer, rubber, synthetic resin, or metal. The deflector 39 is manufactured by machining or the like.

  A labyrinth seal 33 is provided on the deflector 39 and the outer ring 37 on the deflector side. The labyrinth seal 33 can be made of non-metal such as elastomer, rubber, synthetic resin, or metal. The labyrinth seal is manufactured by machining.

  When the labyrinth seal 33 can be removed, the diaphragm side of the labyrinth seal is manufactured as a separate part and fixed by fitting, screw fixing, an adhesive, or the like.

  A sealing liquid supply passage 34 through which fluid can be sent to the closed annular expansion space 32 of the labyrinth seal 33 is provided. The seal liquid supply path 34 is manufactured by drilling, welding, fitting, screws, or the like by a machine or an instrument.

A groove for the contact type rotary seal (38, 35) is provided in the outer ring 37 or the inner ring 43 so that the contact type rotary seal can be attached to the attachment portion of the contact type rotary seal (35, 38).
As the fixed seal 31, an O-ring or the like is used.

  In the case of the manufacturing method sent from the deflector 39 side, the sealing liquid supply path sent to the closed annular expansion space 32 is manufactured by a manufacturing method similar to the manufacturing method of the sealing liquid supply path 34.

  By configuring as described above, it is effective to extend the life of the slewing bearing in a machine that uses the slewing bearing that can rotate the movable portion with respect to the fixed portion.

30 ... Bolt 31 ... Fixed seal 32 ... Closed annular expansion space 33 ... Labyrinth seal 34 ... Seal liquid supply path 35 ... Contact-type rotary seal 36 ... Gear teeth 37 .... Outer ring 38 ... Contact-type rotary seal 39 ... Deflector 40 ... Closed annular space 41 ... Rolling element 42 ... Lubricating oil or grease supply path 43 ... Inner ring

Claims (4)

  Seal means for defining an inner ring and an outer ring, a row of at least one rolling element disposed between the inner ring and the outer ring, and a closed annular space in which the rolling element is disposed between the inner ring and the outer ring The labyrinth seal is fixed to the inner ring or the outer ring, and the closed annular expansion chamber in the labyrinth seal is provided outside the closed annular space of the rolling element. A slewing bearing that seals the expansion chamber with semi-solid, liquid, or gas.   Seal means for defining an inner ring and an outer ring, a row of at least one rolling element disposed between the inner ring and the outer ring, and a closed annular space in which the rolling element is disposed between the inner ring and the outer ring A slewing bearing fixed to the inner ring or the outer ring and having at least a labyrinth seal structure.   Seal means for defining an inner ring and an outer ring, a row of at least one rolling element disposed between the inner ring and the outer ring, and a closed annular space in which the rolling element is disposed between the inner ring and the outer ring And a slewing bearing fixed to the inner ring or the outer ring and provided with at least a labyrinth seal structure on the lower surface of the deflector and the inner ring or the outer ring.   Seal means for defining an inner ring and an outer ring, a row of at least one rolling element disposed between the inner ring and the outer ring, and a closed annular space in which the rolling element is disposed between the inner ring and the outer ring The labyrinth seal is fixed to the inner ring or the outer ring, and provided with at least a labyrinth seal structure on the lower surface of the deflector and the inner ring or the outer ring, and the labyrinth seal is disposed outside the closed annular space of the rolling element. A structure-slewing bearing in which the closed annular expansion chamber is provided, and the closed annular expansion chamber is sealed with a semi-solid, liquid, or gas.

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